Celebrating an anniversary of a watch classicFor 20 years, the Perpetual Calendar has been the defining feature of the Glashütte Original Senator collection

The Perpetual Calendar combines the pinnacle of horological expertise and maximum functionality in a truly unique way. 20 years ago, Glashütte Original gave the complication a face that is a firm feature in the manufactory’s Senator collection to this day. It was in 1999 that the Senator Classic Perpetual Calendar first presented the different calendar elements as elegant puristic windows – instead of the previously customary circular displays. This harmonious arrangement has featured in every Perpetual Calendar model of the Senator series since. Numerous editions over two decades highlight the successful evolution of this classic from the Saxon manufactory.

The Senator Classic Perpetual Calendar from 1999 constituted a genuine milestone for the Glashütte Original brand, combining as it did in such innovative fashion the classic aesthetic of the Senator line, launched two years earlier, with the complex mechanism of the Perpetual Calendar. This mechanism guarantees a precise display of the date, weekday and month up until the year 2100 at least, and even takes leap years into account. In theory, the model does not require manual correction until the turn of the next century.

Framed by a rose gold case, complete with fluted bezel, the Senator Classic Perpetual Calendar presents its calendar displays on a silver dial. The Glashütte Original Panorama Date, the newly developed window displays for weekday and month, the convenient leap year indicator and the moon phase display are favourably arranged on the watch face alongside the hour, minute and central second hands. Clear, tidy and perfect to read – from that moment on, this unmistakable design became one of the hallmarks of the Senator watches with Perpetual Calendar.

The new model from Glashütte and the clear design of this puristic yet highly complex timepiece met with great enthusiasm from the trade press, dealers and watch aficionados. Of course, it was not just the exterior that set out to impress. At the heart of the watch operated the exquisitely finished manufactory Calibre 39‑50 with 48 jewels, a 40-hour power reserve, skeletonized rotor with 21 ct gold oscillation weight and swan-neck fine adjustment. It came as little surprise then in 2000 the Senator Classic Perpetual Calendar won its first "Uhr des Jahres" (Watch of the Year) award for Glashütte Original, as voted for by the public, and later went on to gain huge popularity for its stainless steel versions. Its successor in rose gold with a flat bezel was launched in 2001 under the name Senator Perpetual Calendar.

New movement and strong design impulse

A fundamental redesign was premiered in 2005: The automatic Calibre 100-02 took the place of the Calibre 39-50. In addition to all the calendar functions, the new model boasted not only an extended power reserve of 55 hours, but two other innovations in the shape of its convenient reset function and the rotor that winds up both ways. This next version of the Senator Perpetual Calendar, which included a particularly advanced movement for its time, upheld the tradition of the established dial division with window displays. Its champagne-coloured face and the elaborate guilloché dial gave the timepiece a striking look. Until then and in subsequent years, the product developers at Glashütte Original changed only small details in the design of the watches.

Their new edition of the Senator Perpetual Calendar, which was launched in 2012 with the same movement, the much-loved silver dial and the familiar calendar layout, introduced a completely new look, however: The case was now made of red gold rather than rose gold, and Roman numerals and a black railroad chapter ring were incorporated. Most eye-catching of all, however, were its blued pear-shaped hands.

Success stories 'par excellence'

In 2017, the Senator Excellence Perpetual Calendar has captured this distinctive look. The bezel, which initially had a three-layered design in the 1999 original, appears notably thinner, making significantly more room for the silver-grainé dial in the 42 millimetre red gold case. This change also created space for the reworked and more clearly presented leap year display to take up position below the 12 o'clock index. As an auxiliary dial with a scale of 1 to 4 and counter-clockwise rotating hands, it provides the clearest possible readability not only in the accentuated leap year. The new curved frames around the Panorama Date, the weekday and month windows and the distinctive rounded moon phase display at 8 o'clock also enhance its optical impact.

Just as impressive as the outward appearance are the exceptional mechanics within: The Senator Excellence Perpetual Calendar is powered by the Calibre 36 that was launched the year before. The well-conceived construction of the movement guarantees stable rate behaviour and ultimate precision thanks to its silicon balance spring. A single spring barrel ensures a power reserve of at least 100 hours. As with all Senator Excellence models, Glashütte Original guarantees excellent quality of each and every watch by means of a demanding long-term test and certification.

The Perpetual Calendar in the Senator collection from Glashütte Original is a special success story for the time-honoured Saxon brand. And the story is far from over. The manufactory penned its latest chapter in 2018 with a special edition of the Senator Excellence Perpetual Calendar, limited to just 100 watches. With its skeletonized dial, this exclusive white gold model offers further insights into the fineness of the Calibre 36-02. It masterfully draws attention to the characteristic window displays of the Perpetual Calendar and is thus a worthy representative of an era that first began 20 years ago.